No other disease condition with the high incidence of prostate cancer has so many alternatives with so few certainties. Localized prostate cancer (LPC) can be treated with one or more of several modalities including observation alone, surgery, cryosurgery, hormonal therapy, brachytherapy, or external beam radiation therapy. There are no completed, randomized studies of these treatment modalities. The complications of prostate cancer treatment, sexual, bladder, and bowel dysfunction cannot be easily compared between modalities. There is a growing body of evidence that men with LPC conduct the decision making process by considering their personal characteristics and factors which may be much more influential than any medical factor. A tailored, decision support system has been developed and pilot-tested to enhance men's personal factor clarification, search for information and experiences in expert consultation with physician specialists. The purpose of this randomized study is to compare decisional conflict and satisfaction in men receiving the Personal Patient Profile - Prostate (P4) and traditional patient education strategies. Sub-objectives include comparisons of decisional control shift, quality of life and resource utilization. An ethically and racially diverse sample of 498 men with localized prostate cancer who are preparing for a planned consult visit with a urologist and/or radiation oncologist in which treatment options are discussed. A multi-site trial will be conducted in geographically diverse locations in North America. The intervention will be delivered in both clinician offices or in participant's homes with broad-band Internet access.